Novel Terpenoids with Potent Cytotoxic Activities from .

A novel sesquiterpene dimer, spirocommiphorfuran A (); two new cadinane sesquiterpenoids, commiphorenes A () and B (); along with three known terpenoids (⁻), were isolated from . The structures of these new compounds were characterized by NMR, HRESIMS, quantum chemical computation, and X-ray diffraction analysis. Compound features a 7-oxabicyclo[2.2.1]heptane-2-ene core, representing the first example of germacrane-type sesquiterpene dimer fused via a spiro ring system. Compound is a novel sesquiterpene with a completely new carbon skeleton, which is characteristic of an additional carbon attaching to the cadinane backbone via a carbon⁻carbon bond. Additionally, compounds and exert acceptable cytotoxicity toward normal cells and high selectivity in cancer cells, especially in HepG2 cells.